Railway traffic controlling apparatus



Sept. 7, 1943. c. H. LAY

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Dec. 11, 1942 2 Sheets-Sheet l m m M m m1 in m H m J T N m w m WI w I J 4 WW0 @m D1 1 1W .1 i i i. i I! f m F UHL HI m: I 0 m a u m m 2 s W M i i M 5 2; m w w AL u .1! U W m @1 w W? w 3 W/ P 7? wfl i w 055 a 55 W M M u n 7 WW N w m w n L m 5 Wm r IIII l.

' Sept. 7, 1943. c. H. LAY 2,328,657

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed D60. 11, 1942 2 Sheets-Sheet 2 I d i '52 -H i if I 1 A A A'A' I I '54 I w i 57719 INVENTOR L (Earle? 19. [0y

, zafaz 1 Hff ATTORNEY Patented Sept. 7, 1943" vs D fsiArE si PM RAILWAY TRAFFIC CONTROLLING a APPARATUS P CharlesH. Lay, Swissvale, Pa.) assignor to The is Union Switch and Signal Company, Swissvale,

2a., a corporation of Pennsylvania 7 l 7 Application December 11, 1942, Serial No.1468,606 V t 6 Claims. (claw-3).. j

My invention relates to railway traflic control ling apparatus, and more particularly tocircuits for use in connection with a centralized trafiic 7 control system for the control of railway signals United States to L. v. No. 2, 229,249;issued ,the track switches 'lW and 3W; respectively;

which portions may be combined by placingFig} 1A at ,the left of Fig. 1B"to"i1lustrate a typical passing siding in astretch 'o'f single track rail Wayi Theseviews also'include in diagrammatic formt-he circuits for the track relays for the stretch;--and a route circuit network controlled by the track relays and 'conforming to the track layout comprising the line circuits for control: ling the opposing entrance signals ZRA and ALLA for ghverningtrafiic over thelower maintr'ackt January 21,1941, for Remote control systems. -1

" One feature of my invention resides in the provision of reversible line circuits for 'the control of the entering signals, together with means io'r preventing a signal which ha been'cleared from being putto stop asthe result 'of aninadvertent attempt by'the -operatorto cleara conflicting signal controlled by a "different" lever, "and in respect tothis fe'ature,-' myj inventionis an improvement upon that disclos'ed in Letters Patent 0f the United States to :H. S. Young, No. 2 282,841;

issued May 12, 1942; j- Railwa y'traffic con'ftrol v ling apparatus;

' One object of my invention resides in the provision of a system of route circuits,corresponding to the two routes which the passing tracks afford; for controlling the opposing entering signals so that the condition ofeach is; dependent upon that of 'the oth er when the track switches have been positioned to establish a route through" both ends of the siding, but not otherwise.

further object-of my invention resides in the provision of means for interlocking the code responsive relays by which the opposing entering signals are manuallygoverned in such a manner as to facilitate their control by composite codes, by meansof' which ias -'explained iii-the above-mentioned Lewis" pater-it; the operation of the track switch to anew po sition -and the-clear ing of thesignar'governing trame movements over the route-thereby established, is efiec ted iil le operation. a V. g I I sha'll'describeone form of apparatus embody ing my invention, and shall then point out the" novel features thereof in claims. ,7

Referring to the accompanying drawings l igs 1A and 13 include a single line tra'clg diagram representing portions of railway track including and also those for controlling'the corresponding signals 2R3 and 41B which govern trafiicmove rn eht's inf-opposite directions over i the upper 01 side"tracl FigQ'ZA' shows the circuits" forthe code con trolled relays controlled by a station unit No'. 1 ofthe centralized traifie control system, for effectin'g the manual control of the'track-switch lW and of the associated entering signals 2RA and ZRE, as' Well as of the corresponding leaving signals ZLA and 2LB, thiyvlew corresponding generally to the one illustrating similarly desig nated Ielaysand comprising a portion'of *Fig. 8 of the a Lewis patent hereinbefore referred to; Fig. 2B shows a similar station unitNoJ'Z located at the other end "of the. siding for (zon trolling the track switch 3W, the entering signa'lst lLA and @LB and the leaving signals 4RA and 4RB. l i 2 Similar reference characters refer to similar parts in eachof the several views. 7 It is to 'be understood that those relays shown herein which bear designations similar to those of: the relays of the Lewis patent and for Wh'iiih thezcircuits are not shown in the present'application function like the corresponding relays of the patent. Thus the relays ZRMR and 4LMR areapproach locking stick relays which are ener gize'd only when theassociated signals 2R and 4L are at stop, like the relay RMR and LMR of 9 of the patent; relays IMP'and 3MP correspondfvvith'relay MP of Fig. 8 of 'the patent; relays NWS, RWS,"LHS and RI-IS are'the codecontrolled switch'and signal stickrelays controlled over connections to terminals 8| to 86 of the station coding units as in Fig. 8 of the patent, while the relays NWP and RW]? are normal and {reverse switch'indication relays which may beeither simple'rep'eaters indicating the normal and reverse positions of the track switch like cuit for the pole changer relay 4RPC. When erned by the code controlled relay 4RI-IS, and the signals 2LA and ZLB by the corresponding Q relay 2LHS.

It i thought that my invention may be more readily understood by a description of its operation under different assumed conditions, and accordingly, starting with the apparatus in its normal condition as shown, it will first be assumed that the operator transmits a control code to station No. l to pick up relays l NWS and 2RI-IS, forthe purpose of clearing signal ZRAior a trainmovement over theroute including sections IT, 2T and'BT of the lower main track. In Fig. 1A, the energization of relay ZRI-IS completes a circuit from one terminal B of a suitable local source of currentat its front contact through the winding of a directional relay ZRF and the back contactfi of-a' lockout relay ZRZ to the other terminal C ofthe same source.

It is to be understood that separate sources having corresponding terminals B and C are provided at stations'Nos. l and 2, and that the terminals C of the two sources are connected-together at times-over connections afiorded by one or more of the line wires of the route circuit network. Normally theterminals B of the two sources are also connected together, over a circuit: extending from terminal B in Fig. 1A through'relay ZRZ over wire l0 and thence through relay QLZ to terminal B in Fig. 1B. 'As

shownin the drawingsythis circuit includes oppositely connected rectifier elements which serve to'limit the flow ofcurrent to a negligible value eventhough the voltages of the two sources are unequal. .It follows that normally relays 2RZ and iLZ are both deenergized, and since the back contact 6 -of.relay 2R2 is closed, relay ZRF picks up in response to the energization of relay ZRI-IS and energizes the signal relay ERH in series with relay 4LZ, over the established route circuits, This route circuit may be traced from terminal B, Fig. 13, through relay 4LZ, front contact 'l of relay. lLMR, back contacts 8 and 9 .of relays lRPC and 4LF, front contacts of relays 3T1, 1'3NWPand 3NWS, wire lib-front contacts oifxrelays 2TR, INWS, INWP and ITP, front contact I l of relay ZRF, through relay-2RH, front contacts [2 andl3 of relays ZRHS andZRF and thence over the return portion of: the route circuit including wire M and similar to the portion already traced to terminal C at back contact l5 of relay 4RPC. his to be understood that sincethe flow of current throughrelayZRI-Iis from right to left,its polar, contacts will be operated to their right-hand or'reverse position to energize relay ZRAHR in the reverse direction, causing: signal 2RA to indicate caution.

' The-ienergizatijon of relay -4LZ prepares a circuit; ior'relay-4RPC at front contact I6, Fig. 1B, and; opens the circuit for relayflLHS at back ill a signal lLB to stop. When the train; passes section 4T and vacates section 3T, the operator contact' ll, Fig. 2B It follows that a code re-' ceived at-station No. 2 for energizing relay tLI-IS would be ineffective; relay 4RHS,'howev er-, may be energized topick up relay iRAHR to clear the advance signal 4RA, and to complete a cirrelay 4RPC becomes energized, its contacts 8 and I5 pick up to reverse the polarity of the current supplied to relay ZRI-I, so that relay 2RH will close its left-hand polar' contacts to energize relay '2RAI-IR in the normal direction, causing signal ZRAto indicate proceed 7 e It'will be noted that if the leaving signal lRA is 'cleared'when the entering signal ZRA is at stop, that is to say, prior to the energization of relays ZRH and 4L2, relay 4RPC remains released; If relay GRPC should pick up before relay 2RF becomes energized, a circuit would be completed from terminal B, Fig. 1A, through relay ZRZ over, back contact I l of relay 2RF and wire Ill to terminal C at front contact 8 of relay lRPC, and relay ZRZ would pick up to open its back contact in'the circuit for relay ZRHS, Fig..2A, which would prevent the clearing of signal ZRA, but this is avoided because relay 7 4RPC is preventedfrom picking up until after relay ZRZ is disconnected from, the route cire.

cuit by theoperation of relay ZRF. r

-I- shall next assume that signal ZRA indicates caution to control a train approaching from the left; that signal RA is at stop; and thatthe operator sends a code including elements for" picking up relays BRWS and, lLI-IS for the purpose ofreversing switch 3 and clearing signal SLB for a train approaching from;.the right. Initial1y-relay SNWS will release and only relay 3RWS will pick upin response to, delivery element of the code,. thecircuit for relayJiLHS.

being open at contact I1, but the release of relay ENWS removes relay 4L2 from the route circuit, establishing connections directly from terminalsB and C to wires l0 and I4 at its back contacts, so as tomaintain relay ZRH energized in the reversedirection, and it follows-that the energization of; signal ZRA is not interfered with. RelayALZwill release' and then relay ILHS-will pick up,.the duration of the delivery element being sufficient ,for' the purpose, since; none of the relays involvedare slow acting. Re-

lay dill-IS, at contact !8,-conn ects terminaliB to:

one terminal of relay flLF, the other'terminal of which is connected to terminal C at back con-- tact I6. ofrelay, ALZ, so that relayfiLFpicksup; Relay 3RW S operates switch '3W to reverse in: the usual manner, whereupon the "reverse ine;

dication relay SRWB picksup, completingaroute circuit for relayALI-L extending from terminal B,'Fig. -1A,,ov er a back contactof relay--IRWS, wire IiL- front contacts of relays 4TB, 3RWS.

BRWP and 3TP, front contact 9 of relay ALF through relay lLl-I, over contacts 20;-and 2i Off relays dLHS an dALF and the return portion of' the route circuit including wire 22 and extending to terminal C at a back contact of relay IRWS.

Relay ALI-(therefore. becomes energized in the reverse direction and in turn energizes relay lLBHR in the reverse direction to cause signal lLBto indicate caution. p v Assuming now that the train approachingfrom the right enters-section 3T; relays 3 B, ALHS,

iLH, 3TP 'andALF will release, in that order,

deenergizing relay lLBI-IR -and thereby restoring may senda code to releaserelay '3RWS and "to energize relays 3NWS and iRHS, in order to clear signal 4RA to permitthe train approachingfrom the left to pass-through section-3Tn When' relay 3NWS picks up, the'route circuit for relay 2Rl-If'is sliifted to extend fromwire it! over the acades-7,

lower front contact ofrel'ay fand'the back contact of relay through-relay 'ALZ to l terminal Bfthat is, relay lLZ inserted into the route circuit 'in- 'seri'e's with r'eIa yZRI-I. "Relay BNWS operates'switch 3W to normal, causing the normal indication relay SNWP to pi-ck up to shift the route. circuit for relays 2B and LZ' to the path including frontal-contact 1 of relay ALMR, this. route circuit being the same asthat already traced at the beginning of this description; Relay SNWP also completes acircuit, notshownd for relay QRAHR, whereupon signal RA is caused to indicate caution or proceed and then may 4RP'C picks causing sig nalERAtoindicateproceed;-

It might happen'thatth'e operator would-inadvertently send a codefor clearing signal ALA in place of one for clearing signal ARA, under the conditions just described, in case relays" 3NWS andlLI-IS would-pickup.

Relay' 3NWS would insert relay tLZ' intojthe route circuit as in the preceding case, butthe opening of its back contact I! now wouldcause relay 4LI- IS to release. Relay SNWS operates switchdw to normaland relay SNWP establishes the route circuit, as 'loefore, but signal 4RA of course remains at stop, and it will be seen that the apparatus is left inthe same conditioners if relay ALI-IS had not been operated by the code,

In other Words, the clearing of a' sig nal for'one direction nullifies any attemptto clear the spins; ing signal for the same route.

two sources are not connected together at any time insucha way that their voltages are additive.

Althoughlhave infthe foregoing described only a few of the possible operations involving l the control of thesign'als at itwo adjacent stations, it

is be'lieved thatin view of the symmetry of the .circuitsfor twodirections the operation of the apparatus-oi my invention under other assumed-- conditionswill be readily understood'without' furthe'rdescription. l

- AlthoughI- have herein shown-and described only one form' of railway traflic controlling "ap It will next be assumed that the train approach;

ing from' the left stops in section ZTQand that the operator sets up a run-aroun route 'for the opposing train by sendingfa code to reverse switch 1 and to cleansign'al ZLB and aisecond code to reverse switch 3, and clear signal ALB, Upon the completionof the operation-of the track switches to reverse, the route fcircuit including relay 4LH; alreadytraced, will be extended from wires [9 and 22 over front contacts of relays IRVVP and -lRWSto the back contacts H and I3 of relay ZRF, and-will be completedfrom back contact H over the lower back contact of relay ZLPC and the front contact of relay ZRMR.

through relay ZRZ to terminal B, and from back contact l3 over the upper back contact of relay 2LPC to terminal C. Relay ZRZ will therefore be energized in series with relay iLl-I and will complete the-circuit for relay'ZLPC to reverse the polarity of the current supplied to relay dlLH,

manually controllable switch and signal control means'at each station for governing the op eration ofthetrackswitch and signals at that station, a routecircuit' network of interconnected circuits connecting said stations'including a signal circuit for, each signal, each signal circuit including contacts'contrdiedby the switch and signal control m'eansat the same station and also including 7 contacts controlled by the switch control means that is, relay ZRZ will function like relay 4L2 already described, to lock out the code control of the opposing signal and to so control the associated pole changer relay as to avoid any connec tion over the route circuit network which includes the two sources of current in series.

A further feature of the circuits related to the foregoing is provided by making relays ZRF and 4LF slow release. Assuming that relays ALF: and 4LHS are picked up, energizing relays ZRZ and lLH in series, and that relay ZLPC is picked up i so that relay 4LH is energized in the normal direction. If relay lLI-IS then releases to open the route circuit at contact 20, relay ZRZ releases, and in turn releases relay ZLPC. Relay 4LF becomes deenergized due to the opening of front contact [8 of relay 4LHS, but its winding is short circuited over back contact 18 and its release is thereby delayed until after relay ZLPC releases. It will be seen that like terminals of the two current sourcesare connected together over the route circuit network only when the pole changer relays are released, and that'the atthe other station, a lookout relay at each eta-- tion controlled over said-route circuit network by the signal control means at the other station and-adapted to be energized only when the switch controllrneans at the two stationshave been conditioned to establish a route thrq-ugh'bothstatlons'l and-means preventing the operation of the signal control-means at each station when thelo'ckout relay fatthe 'samestation is energized.

*2. In a centralized 'ti'aific control system for governing trafiic movements over a stretch of railway track including two track switches located, at different stations and adapted to establish traflic routes through both stations when operated to corresponding normal or reverse positions, a signal for each route at each station,

manually controllable switch and signalcontrol means at each station for governing the operation of the track switch and signals at that station, a signal circuit for controlling each signal including contacts controlled by the signal control means at the same station and contacts controlled by the switch control means at bothstations, and lockout means controlled by each signal control means when energized for preventing the energization of the signal control means at the other station when the switch control means at the two stations have been conditioned to establish a route through. both stations.

3; Infla centralized traific control system for governing traffic movements over a stretch of railway track including two track switches 10- 1 cated at different stations and adapted to establish vtraific routes through both stations when operated to corresponding normal or reverse positions, a signal for each route at each station, manually controllable switch and signal control means at each station for governingthe operation of the track switch and signals at that staclaims without departing irom the spirit and at both stations, means ,for extendingfthe circuit for the signal relay at, one station to include'in series therewith the lockout relay at the other; station when the switch control-means at 'bothstations have been operated to corresponding normal or reverse positions, and meansjcontrolled by each lockout relay when energized forpreventing-theienergization of the, associated signal con-,-

/ -4. In combination with a stretchoiflsingle-track railway. including two" track; switches-connected bypassing tracks, entering signals for governing, trafiic movements over each routev provided by one track switch and leading intosaid passing tracks, leaving signals for governing traflic movements over each .route provided by the other track switch and leading out of said passing tracks,.independently operableswitch and signal control means associated with each 'trackswitch for controlling itsaoperation and for selectively clearing that signal'which governs traffic movements over the route established by such operation, a -pole changer controlled by each leaving signalfor reversing the polarity of the current supplied to that entering signal which governs traffic movementsinto the route governed -by;such leaving signal, and means controlledijointly by the, switch control means for the two track switches for'preventing the operation of said'pole changer except when a route is establishedwhich'includes both aized signal relay for controllingpsaid entering trolling its operation and for selectively clearing that signal which governs traific movements over. the route established by such operation, a polarsignals, a pole changer controlled by said leaving signals for reversing the polarity supplied to said signal relay when a leaving signal is energized; and means controlled by the switch control means associated with said leaving signals for prevent,-

ing the operation of said pole changer except when a route is established which includes both track switches in corresponding positions.

6. In a centralized trafiic control system .forastretch of single track railway-including two track switches at spaced locations connected by passing tracks with signals at each location for governing trafiic movements in opposite directions over the track switch at that location, said' system including switch and signal control means at each location manually controllable from acentral oifice for governing the operation of the track switch and signals at that location, withline-circuits connecting the two stations forenergizing those signals at eachlocation which. govern traflic movements toward the other location in accordance with said manual control, the combination, of a lockout relay at each station effective when energized to render the control means for the signals controlled over said line V circuits non-responsive te said manual-control; with means for energizing the lookout relay at each location over the line circuit ior a signal at the other location when such signal has been cleared for a trafiic movement over a route in;-

cluding one passing track, such route aincluding both track switches in corresponding positions,"

and means for releasing said energized lockout; 

